Albree Trulog Duplex Circular Logarithm Table


This is Norman Albree's pilot model for a two-sided circular logarithmic chart. The side labeled A has a double logarithmic scale arranged in a spiral of seven turns. Its outer edge is marked from 1 to 3.15. The inner edge is marked from .0 to .5. The side labeled B also has a spiral double logarithmic scale, marked from .315 to 1 on the outer edge and from .5 to 1 on the inner edge. A clear plastic cursor folds over the edge of the instrument and is pivoted at the center on both sides.

The A side is marked inside the fourth spiral: 19©45, and at the center: TRULOG DUPLEX. The B side is marked inside the fourth spiral: 19©45 (/) G. N. Albree, and at the center: G. NORMAN ALBREE. The instrument was received with a hand-sewn brown leather pouch. George Norman Albree, the inventor and donor, was an aeronautical engineer. See also MA.335484 and MA.335486.

Date Made: after 1945

Maker: Albree, G. Norman

Location: Currently not on view

Place Made: United States: Massachusetts, Boston

Subject: Rule, CalculatingChart, LogarithmicMathematics


See more items in: Medicine and Science: Mathematics, Science & Mathematics, Slide Rules


Exhibition Location:

Credit Line: Gift of G. Norman Albree

Data Source: National Museum of American History

Id Number: MA.335487Catalog Number: 335487Accession Number: 321674

Object Name: slide rule

Physical Description: paper (part material)plastic (cursor material)wood (overall material)metal (part material)Measurements: overall: 1.5 cm x 26.2 cm x 24.5 cm; 19/32 in x 10 5/16 in x 9 21/32 in


Record Id: nmah_1215052

Our collection database is a work in progress. We may update this record based on further research and review. Learn more about our approach to sharing our collection online.

If you would like to know how you can use content on this page, see the Smithsonian's Terms of Use. If you need to request an image for publication or other use, please visit Rights and Reproductions.